From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 1357E3C4178; Tue, 16 Jun 2026 17:40:18 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781631619; cv=none; b=VBUPB2QP4MpBt9S5RL1UhhKvNrFbCcoG2n78kC9eowkRteXVaagFHf9yULjqdPJc/70BlUjohrGjeJ2NdHeKV0gZDASw8HQKD3LFVrkeFU/jeAXRUVi1HuCv7Zeat+6ieklDgPkX6V03xLYXbsFAWzTQLigMKOWD248KQZFgSGE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781631619; c=relaxed/simple; bh=YxFPCEt0No1AmGNlp2Bacdkff37VJe+uBX1l0z7tIOM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=Plqxmr+18BaMZBvDQm2hcFxJRkrMwEgx+neqtZrjYLFWRZlXjA+buuS/ogB8ErSZMhom94rv9ysNcmMi4SY6l0KowWBk7veraNPT1fI22+hNuXK5s87bJDIY6hDDVyNHMQa+HSh5uhfHhZBn7hlV06s41t1uCg08uqsiEnxdOAw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=UVGH9VKT; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="UVGH9VKT" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 162B01F000E9; Tue, 16 Jun 2026 17:40:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1781631618; bh=AVks9yqtnzdjy0ZGD2Yrn4PRC63vPGNn5NKa2RSlrFQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=UVGH9VKTmMiTsz9t7g8t4lQoKrY7xbgDhzeMRrap87JP891aQy8uzL6QpPGvhZv1u YU6FgKHh7IQ9ryVZLzRujocZU7zfmGH4Gb5JAyT2Er3ZTewO79Mmt4hCcS60qG26B1 aSVwUarFjMpOiMT5JAZ+O1N2xrJ9h+1XS3iBS8qc= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Breno Leitao , Allison Henderson , Jakub Kicinski , Sasha Levin Subject: [PATCH 6.1 255/522] rds: mark snapshot pages dirty in rds_info_getsockopt() Date: Tue, 16 Jun 2026 20:26:42 +0530 Message-ID: <20260616145137.884996400@linuxfoundation.org> X-Mailer: git-send-email 2.54.0 In-Reply-To: <20260616145125.307082728@linuxfoundation.org> References: <20260616145125.307082728@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Breno Leitao [ Upstream commit 512db8267b73a220a64180d95ab5eebe7c4964a8 ] rds_info_getsockopt() pins the destination user pages with FOLL_WRITE and the RDS_INFO_* producers memcpy the snapshot into them through kmap_atomic(). Because that copy goes through the kernel direct map, the dirty bit on the user PTE is never set, so unpin_user_pages() releases the pages without marking them dirty. A file-backed destination page can then be reclaimed without writeback, silently discarding the copied data. Use unpin_user_pages_dirty_lock() with make_dirty=true so the modified pages are marked dirty before they are unpinned. Fixes: a8c879a7ee98 ("RDS: Info and stats") Signed-off-by: Breno Leitao Reviewed-by: Allison Henderson Link: https://patch.msgid.link/20260608-rds_fix-v1-1-006c88543408@debian.org Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- net/rds/info.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/rds/info.c b/net/rds/info.c index b6b46a8214a0a5..b3ee5f8238c44d 100644 --- a/net/rds/info.c +++ b/net/rds/info.c @@ -235,7 +235,7 @@ int rds_info_getsockopt(struct socket *sock, int optname, char __user *optval, out: if (pages) - unpin_user_pages(pages, nr_pages); + unpin_user_pages_dirty_lock(pages, nr_pages, true); kfree(pages); return ret; -- 2.53.0